Issue 67

M. Selim et alii, Frattura ed Integrità Strutturale, 67 (2024) 205-216; DOI: 10.3221/IGF-ESIS.67.15

which prevents surface separation after contact. A coupling constraint was used to prevent axial slipping of the external case. The specimens were fixed from one end, allowing free axial movement at the other end at which the load was applied. The boundary conditions were applied to both ends through two reference points. The load was applied through two steps; the first steps included the application of the pre-tensioning force in cables, while a cyclic loading was utilized in the second step. A verification study on previous research was performed followed by a parametric study. A 50 mm mesh size was considered in the current study. The steel core plate and other model components were simulated using a bi-linear elastic plastic stress-strain relationship, considering strain hardening effects as per AISC 358-16.

External case

Cross-arm

Cable

Rib

Cable

fill

Core plate

( b ) Model parts

(a) Assembeled model

Figure 1: BRB specimen details.

Verification In this step, the model was verified against the experimental results of a BRB specimen tested by Wang et al [40]. where the tested specimen dimension (U-V1) is 1650 mm in total length, with a core plate yielding segment length (Ly) of 900 mm and width (w) of 10 mm as shown in Fig. 2

Figure 2: U-V1 specimen dimension.

The specimen underwent a cyclic load protocol. The initial axial stiffness in the elastic stage was measured using a strain amplitude of 0.75 y  . for the first four cycles. The subsequent loading phases consisted of variable strain amplitude (VSA) loading with increasing amplitudes, followed by constant strain amplitude (CSA) loading with a 2.0% amplitude. The

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